North Korea launched a controversial long-range missile in what it said was an attempt to launch a rocket into space.
Regardless, the rocket broke apart after exploding in the air.
You can read up more about this particular incident here.
But everyone knows North Korea is aggressive, anti-social, and usually tries to kill a few South Koreans every year. Honestly, I have lost track of the count of the number of South Koreans killed by North Korean provocations during the time I have been here. Floods from dam reservoirs, submarine sinking, and bombings all perpetrated by North Korea have happened within the last three years.